Relatives of hostages still being held in Gaza will join Prime Minister Benjamin Netanyahu on the inaugural flight of Israel’s version of Air Force One, as the premier heads to Washington, D.C., to deliver a pivotal speech to a joint session of Congress on July 24, Jewish Insider has learned.

The Prime Minister’s Office did not respond to a query about which families would join Netanyahu.

Relatives of the five living American hostages – Keith Siegel, 65; Sagui Dekel-Chen, 35; Omer Neutra, 22; Edan Alexander, 20; and Hersh Goldberg-Polin, 23 – are expected to attend the speech. A spokesperson for the Bring Hersh Home campaign said his parents plan to travel to the U.S. before Netanyahu to hold meetings and speak to the media.

Jonathan Dekel-Chen, father of Sagui Dekel-Chen, said that he will not be traveling with Netanyahu and is still working out his plans.

Sen. Ted Budd (R-NC) plans to invite a member of the Siegel family to attend the address. Several other members of Congress plan to invite hostage families, but would not comment on record because the tickets to the speech have not come through yet.

Julie Fishman Rayman, managing director of policy and political affairs at the AJC, said that they are “working with the hostage families to ensure that their and their loved ones’ stories remain top of mind for leaders in America and Europe. We were glad to help connect family members with Members of Congress on both sides of the aisle ahead of the State of the Union to secure their attendance, and we are doing the same for this high-profile address. The work does not stop until we bring them all home.”

Other hostage families, affiliated with the Hostages and Missing Families Forum, called on Netanyahu to cancel his speech before Congress, saying the prime minister must “prioritize finalizing a hostage release deal.” The forum did not specify which families joined the statement, in light of the plans of several families to attend.

“A speech without concrete action to seal the deal and bring our loved ones home is premature and misses the mark of this war’s top priority – The return of all the hostages,” the forum’s statement, released Monday, reads. 

Netanyahu’s flight to Washington, D.C., will be on “Wing of Zion,” a designated airplane for Israel’s prime ministers and presidents, which has been in the works for a decade. 

Its inaugural official flight was supposed to be to the UAE for the U.N. Climate Change Conference held late last year, to which Netanyahu and President Isaac Herzog were invited. Only Herzog ultimately attended, flying on a leased Israir plane.

“Wing of Zion” is a smaller plane than the El Al jets the Prime Minister’s Office generally leased for long flights, and with the hostage families present, the PMO invited a pool of only six media outlets aboard.

The former Qantas aircraft is a modified Boeing 767 with a redesigned interior and a defense system. The plane has had several test flights, but none were over 3.5 hours. The plane has 80 seats, but only 60 will be taken, out of a concern that it cannot make a transatlantic flight at full capacity, KAN, Israel’s public broadcaster, reported on Tuesday.

Marc Rod contributed to this report.